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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

A study of the hydrolysis of choline ester analogs

Hawbecker, Byron Leon, 1935- January 1962 (has links)
No description available.

Part I: The synthesis of a stable nitronic ester: Part II: Thermal isomerization of the nitronic ester to a spiro-oxazirane / Nitronic ester

Young, Alvin H. P January 1966 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Includes bibliographies. / viii, 64 l illus

Some compounds derived from the ethyl p-diiminosuccinylosuccinate ...

Nelson, John Maurice, January 1907 (has links)
Thesis (Ph. D.)--Columbia University. / Biographical. Bibliography: 1 p. following p. 48.

The transposition of esters and the interdependence of limits

Markel, Paul David, January 1916 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1916. / Biographical.

Hydrogenation of esters

Billica, Harry Robert, January 1947 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1947. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Reactions of bromo zinc malonic esters [I.] II. The pyrolysis of orthoesters /

Anthes, Harrison Inman, January 1942 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1942. / Typescript. Includes abstracts and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Reactions of esters with alkoxides

Spindt, Roderick S. January 1944 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1944. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The enzymic hydrolysis of phosphoric acid esters by barley extracts

Brink, Vernon Cuthbert January 1936 (has links)
[No abstract available] / Land and Food Systems, Faculty of / Graduate

Synthetic studies using B-keto esters

Sum, Phaik-Eng January 1976 (has links)
The dianions of β-keto esters have been generated using one equivalent of sodium hydride and one equivalent of n-butyl1ithium or two equivalents of lithium diisopropyl-amide. The reaction of these dianions with various epoxides was studied. On treatment of lithio sodio methyl aceto-acetate (55) with one and one-half equivalents of ethylene oxide and on subsequent treatment with acid, a tetrahydro-furylidene acetate 95, formed from the cyclization of the intermediate alcohol. Methyl α-(tetrahydro-5-methy1-2-fury1i-dene) acetate (96) was also synthesized by treating the di-anion with propylene oxide. The alkylation of these dianions from β -keto esters with α-chloroethy1 ethyl ether or α-ch1oromethy1 methyl ether was also investigated. This provides a convenient preparation of the precursors to Nazarov's reagent which are very useful in the Robinson type annelation. The preparation of methyl 5 - methoxy-3-oxopentanoate (12 0) could be easily achieved in a single step synthesis by treating the lithio sodio methyl acetoacetate (55) with one equivalent of chloromethyl methyl ether. Similarly, methyl 5-ethoxy-3-oxohexanoate (12 9) and methyl 5-methoxy-3-oxohexanoate (130) were prepared using our dianion reaction. The synthesis of large ring compounds using the internal double alkylation of these dianions with dihalo-alkanes in a one-step reaction was found to be rather difficult. The isolated products were a mixture of the bis β -diketo esters and a y-alkylated mono-halo compound in approximately equal amounts. However, on treatment of the mono-halo compound with one equivalent of sodium methoxide in refluxing methanol, the intramolecular cyclization at the a-carbon was easily achieved. The mono-halo β-keto esters could also be cyclized via their dianions to the cyclic or spiro β-keto esters. / Science, Faculty of / Chemistry, Department of / Graduate

Total synthesis of lavendamycin esters and analogs

Mohammadi, Farahnaz January 1993 (has links)
The purpose of this research was to synthesize 7-bromodeaminolavendamycin methyl ester (11), deaminolavendamycin methyl ester (19), 7-N-isobutyryldemethyllavendamycin methyl ester (54), 7-N-acetyldemethyllavendamycin ethyl ester (64), 7-Nisobutyryldemethyllavendamycin butyl ester (76), 7-N-isobutyryldemethyllavendamycin tbutyl ester (78), 7-N-cetyldemethyllavendamycin phenyl ester(79), and 7-Nisobutyryldemethyllavendamycin isopropyl ester (80).Lavendamycins 54, 64, 76, 80 were synthesized via the Pictet-Spengler condensation of the corresponding tryptophan esters with 7-N-acetamido-2-formylquinolinedione (91) or 7-N-isobutyramido-2-formylquinolinedione (92). 3-Carbomethoxy-l-( 8-hydroxyquinoline2-yl )-4-methyl-(3-carboline (18), and 3-carbomethoxy-l-(5-acetamido-8-acetoxy-7bromo-2-yl)-4-methyl-(3-carboline (109) were also prepared through the Pictet-Spengler condensation of p-methyl tryptophan methyl ester with 2-formyl-8-hydroxyquinoline (103) and 5-acetamido-8-acetoxy-7-bromo-2-formylquinoline (108), respectively.Compounds 18 and 109 were oxidized by potassium dichromate or Fremy's salt to give deaminolavendamycin methyl ester (19) and 7-bromodeaminolavendamycin methyl ester (11) respectively.7-Isobutyramido-2-formylquinoline-5,8-dione (92) was prepared according to the following general procedure. 8-Hydroxy-2-methylquinoline (26) was reacted with a 70% mixture of HNO3 / H2SO4 to produce 8-hydroxy-2-methyl-5,7-dinitroquinoline (39). Compound 39 was reduced by H2 / Pd-C and then reacted with isobutyric anhydride in the presence of sodium sulfite and sodium acetate to produce 88. Recrystallization of 88 with methanol gave 5,7-diisobutyramido-8-hydroxy-2-methylquinoline (98). Compound 98 was suspended in acetic acid and oxidized by a solution of potassium dichromate to give 7isobutyramido-2-methylquinoline-5,8-dione (90). The dione derivative 90 was oxidized by selenium dioxide in 1,4-dioxane to yield the target aldehyde 92. 2-Formyl-8hydroxyquinoline (103) was synthesized through a selenium dioxide oxidation of 8hydroxy-2-methylquinoline (26).Ester 96 was prepared by the Fischer esterification of L-tryptophan with an excess amount of isopropyl alcohol in the presence of dry HCI. L-Tryptophan phenyl ester (97) was prepared through a two-step reaction. NCBZ-L-tryptophan (101) was treated with phenol and BOP reagent in the presence of triethylamine in acetonitrile to yield NCBZ-L tryptophan phenyl ester (102). The N-protected ester was reduced to L-tryptophan phenyl ester (97) by ammonium formate in the presence of palladium on charcoal in N,Ndimethylformamide. Esters 93-95 were obtained by the treatment of their commercially available hydrochloride salts with 14% NH4OH and then extraction with ethyl acetate.The structures of the compounds 11, 18, 19, 54, 64, 76, 80, 88, 90, 92, 96, 97, 98, 102, 103, 106, 108 and 109 were comfirmed through tH NMR, IR, and MS. Elemental analyses of 90, 92, 96, 98, 103 and 106 and HRMS of 98, 19, 54, 76, 95, 109 are also included. 1H NMR are also provided for compounds 39, 94,95. / Department of Chemistry

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